Before last night’s outburst, Murphy was struggling. He entered play in a 6-for-52 (.152) skid over his previous 16 games, sinking his average to .283. He now is hitting .286.

“One of the things I told him the other day: Never in my wildest imagination would I think Dan Murphy would go 3-for-33 with as good a hitter as he is and as good a swing as he’s got,” Collins said before the game.

“I still say at the end of the year we’re going to look up and he’s going to be at .305, so he’s still got a hot streak coming.”

Murphy underwent an MRI exam, the results of which were negative, on Monday for a barking right shoulder. Murphy incurred the soreness during an at-bat the previous day, and he has been prescribed anti-inflammatory medication.

* Collin McHugh, who pitched seven shutout innings in his major league debut last Thursday, will make his next start for the Mets on Monday in St. Louis. The righty pitched last night for Triple-A Buffalo and allowed two runs in 4 2/3 innings and got a no-decision.

* Collins said he hasn’t been told which players will be joining the Mets from Buffalo as September call-ups. But the manager said it’s unlikely there would be significant additions to the roster before Buffalo concludes its season on Monday.

Major league rosters can expand to 40 players beginning Saturday. Pitchers Jenrry Mejia and Jeurys Familia are among the players expected to join the Mets in September.

* Mets starting pitchers entered last night’s with a 2.59 ERA over their previous 14 games, but the Mets were 5-9 over that stretch.

Last night, the trend was reversed. Chris Young struggled, giving up five runs in 4 1/3 innings, and the struggling Mets offense busted out.